[bpf-next,v2,0/3] samples: bpf: Refactor XDP programs with libbpf

Message

Daniel T. Lee Oct. 10, 2020, 6:17 p.m. UTC

To avoid confusion caused by the increasing fragmentation of the BPF
Loader program, this commit would like to convert the previous bpf_load
loader with the libbpf loader.

Thanks to libbpf's bpf_link interface, managing the tracepoint BPF
program is much easier. bpf_program__attach_tracepoint manages the
enable of tracepoint event and attach of BPF programs to it with a
single interface bpf_link, so there is no need to manage event_fd and
prog_fd separately.

And due to addition of generic bpf_program__attach() to libbpf, it is
now possible to attach BPF programs with __attach() instead of
explicitly calling __attach_<type>().

This patchset refactors xdp_monitor with using this libbpf API, and the
bpf_load is removed and migrated to libbpf. Also, attach_tracepoint()
is replaced with the generic __attach() method in xdp_redirect_cpu.
Moreover, maps in kern program have been converted to BTF-defined map.

---
Changes in v2:
 - added cleanup logic for bpf_link and bpf_object in xdp_monitor
 - program section match with bpf_program__is_<type> instead of strncmp
 - revert BTF key/val type to default of BPF_MAP_TYPE_PERF_EVENT_ARRAY
 - split increment into seperate satement
 - refactor pointer array initialization
 - error code cleanup

Daniel T. Lee (3):
  samples: bpf: Refactor xdp_monitor with libbpf
  samples: bpf: Replace attach_tracepoint() to attach() in
    xdp_redirect_cpu
  samples: bpf: refactor XDP kern program maps with BTF-defined map

 samples/bpf/Makefile                |   4 +-
 samples/bpf/xdp_monitor_kern.c      |  60 +++++------
 samples/bpf/xdp_monitor_user.c      | 159 +++++++++++++++++++++-------
 samples/bpf/xdp_redirect_cpu_user.c | 153 +++++++++++++-------------
 samples/bpf/xdp_sample_pkts_kern.c  |  14 ++-
 samples/bpf/xdp_sample_pkts_user.c  |   1 -
 6 files changed, 230 insertions(+), 161 deletions(-)